Windscoop – a common landscape feature here in Antarctica

Strong winds are quite common in Antarctica, and here is no different.  We are currently living beside a small mountain range that interrupts the bulk of the East Antarctic ice sheet from the coast.  Over the ice sheet there is commonly a high pressure system that forces the air to flow to the low pressure closer to the coast.   The greater the difference between these pressures, the stronger the wind.  While we have experienced primarily calm to moderate winds, the average wind speed here is about 20km/hr, which much higher winds in the winter.   These strong winds not only help the station generate power but they also shape the landscape.

Windscoops are a feature common to this part of Antarctica, especially when there are rocks or mountains that are elevated above the ice sheet.  The rocks, which could be considered small mountains, stick out from the ice sheet they are called nunataks.  When the wind from the ice sheet reaches these nunataks, the wind pushes snow up the windward sides (the side where the wind is coming from).  However, on the other side of the nunatak (leeward side), the wind is focused and scours the snow away from the blue ice.  This means that on the leeward side of nunataks, there is often very hard blue ice that is much lower than the snow on the windward side.   Some windscoops are subtle, but most are big.   The windscoop next to the station has almost a kilometer of exposed blue ice and almost a hundred meters of elevation change.  There is a windscoop about an hour snow machine ride from here, that has a wind scoop that is 10s of kilometers long.   So this is a very distinguishing feature in Antarctica.

These windscoops are of interest to us to sample for a number of reasons.  If you drill down into the ice, there is often liquid water below the surface.  It is unclear where this water comes from.  Did the water accumulate on the surface of the ice on a warm day (e.g. lake formed) and then later became frozen over?  Does the water travel down the nunatak below the ice beneath the ice?  When we have drilled into the ice, we have found liquid water about 1 meter (a yard) below the ice.  We plan to sample the water to see if we can figure out the source of the water and what organisms may be living there.

Leave a Reply

Your email address will not be published. Required fields are marked *